How we process workload

Workload of instances are estimated using AWS cloudwatch CPU metrics summary.

Cloud scanner uses a sampling period of 15 minutes, but impacts metrics are returned as impacts equivalent to one hour of use.

This means that instance impacts metrics data returned can be understood as: impact for one hour of use (considering the CPU workload of 15 last minutes).

Why this default sampling period of 15 minutes ?

• It seems sufficient for our current monitoring needs (but maybe we can make it configurable in the future).
• It seems hard to go below 10 minutes (because default period of AWS instance metrics is 5 minutes. You need to activate detailed monitoring (extra feature) for 1 minute granularity: List the available CloudWatch metrics for your instances - Amazon Elastic Compute Cloud).